The graph above shows the distance Mr. Johnson drives over time.
What is the speed at which Mr. Johnson is driving?
A. 7 miles per hour
B. 40 miles per hour
C. 60 miles per hour
D. 80 miles per hour
![The graph above shows the distance Mr Johnson drives over time What is the speed at which Mr Johnson is driving A 7 miles per hour B 40 miles per hour C 60 mile class=](https://us-static.z-dn.net/files/d18/7ea17a9fcd21586743f45fa26c4f4146.png)